Metal door construction



'5 1927. )Apnl E. v. COULSTON METAL DOOR CONSTRUCTION Filed Oct. 19, 1922 fia',

I ATTORAEK Patented Apr. 19277.

EARL V. COULSTON, OF ROCK ISLAND, ILLINOIS.

METAL DOOR consrrworron.

Application filed. October 19, 1922. Serial No. 595,480.

My invention relates to door structures and particularly tov door structures for use wherever metal doors are desirable, as in stoves, ovens or the like.

The object of the invention is to provide a structure simple and economical of.con'- struction and efiicient in the performance of its functions.

,The said invention consists of means hereinafter fully described and particularly set forth in the claims.

Heretofore it has been customary in. con- 'structing doors for ovens or stoves to make nuts were used an outer peripheral frame ofcast 1r0n the central openingofwhich'is filled, for the purposes of lightness and neatness of appearance, with a sheet-metal panel which was often made outwardly convex, also often exteriorly covered or finished with enamel,

and was secured to the frameiby means of bolts and nuts or screws. Another and'flat panel was secured to the inner surface of said frame to cover the hollow space formed by the exterior panel and to impart a smooth and level inner surface to the door. inner panel was also secured to the" frame by bolts and nuts or screws.-

It will be seen from the above customary method of making these doors, that the frame was made by casting and the sheetmetal parts by shearing or stamping, two different processes of manufacture, a feature which contributed materially to the cost of manufacture. Also that inorder to secure the parts, unsightly and projecting bolts and or where screws were used,

the process of tapping'had to'be resorted to, which also contributed undesirable expense of manufacture.

: More specifically, the object ofmy invention is to provide a door which may be made by the single-process of sheet-metal manipuentirely with a cast 1ron lation and dispense use of bolts and nutsor frame and with the screws and theirfattendant disadvantages.

To this end I make the entire door of I sheet-metal and secure the different elements the structure by elementv over and or-othets.

the peripheral portions of bending the metal of one pressing it upon the other to each other at .Other features of my invention will be hereinafter fully described.

The annexed drawing and the following description set forth-in detail certain means embodying the invention, the described This means, however,

the invention ma be applied.

In said annexe drawing:

Fig. 1 represents a plan of a stove or oven door embodying my invention.

Fig. 2 represents, upon an enlarged scale,

Referring first to the embodiment of my; invention illustrated by Figs. 1 and 2,"the

structure comprises an inner flat sheet-metal wall member 1 of rectangular form, and an outer sheet-metal wall member 2 also of rectangular form but of greater dimensions than member 1. The peripheral portion of member 1 is, first bent at right angles to the plane of thexsheet, as shown by the dotted lines, Fig. 2, to form a flange 3 of dimensions such that itwill snugly receive member 2 when laid therein.

Said member 2 is, however, first subjected to a stamping or bending process to form an intermediate convex exterior surface 4 and a surrounding flat peripheral flange 5.. Member 2 is then laid upon member 1,'as shown in Fig. 2,. and the flange 3 bent down over flange 5 and pressed securely, thereon, by suitable means, so as to bring the eripheral portions of the two members firm yin contact with and secure them to each other, the intermediate or central portions of themembers being separated from each other, as shown. I

The above described structure and method of assemblage is suitable for adoption when constituting but part of the different forms in which the principle of unenameled sheet-metal is used for the outer member 2.

Should an enameled sheet be used for the outer wall in the above described structure, the enamel upon the exteriorand inwardly from the inner edgeof the flan e 3, would 'crack, when said flange is presse upon suchenameled sheet, and unsightly cracks and imperfections "in the enamel surface would form on the back thereof a peripheral rec'- tangular depression 6." I- then take a rectangular unenameled sheet 7, formed with a central rectangularopening 8 and form a flange 9 thereon at rlght angles thereto, as shown in dotted lines in Fig; 4. The outer enameled sheet-metal 'wall member 10, simi lar to the previously described -member 2,

" is then laid on the back of member 7 and the member 6 then laid on the back of member 10 withtheir peripheral flanges in contact. The flange 9 is then bent over and pressed I -upon the back of the member 6 and into the 4 of member 7.

i so

wallmemb r 'de ression 6'. The latter is made of a depth su stantially equal to thethickness of the member 7',-so that the exterior surfaces of the members 6 and 7 will be flush with each other as shown in Fig. 4. The outer portion of member 7 projects inwardly from the edge of the structure, a greater distance than does the inner portion thereof,- so that when pressure is exerted upon the entire inner portion, in assembling, any crack or other imperfection onthe outer enameled'surfac'e pr0- duced' thereby will be covered up by the inner peripheral portion of said outer part door 'composed entirely of sheet-metal is produced, the arts of which are secured to each other wit out the use of bolts and nuts or screws. A finished and attractive appearanceis thereby imparted to both the exterior and interior of such door..

What I claim is: i

1...In a door structure, the combination of a primary inner sheet-metal wall member; a secondary inner sheet-metal wall member; and an outer, sheet-metal wall member; said primary inner member being provided with a peripheral depression upon its inner side;

saldsecondary memberbeing bent around the peripheral portions of said primary and outer members to secure same in contact with each other; the inner portion .of said secondary member lying in said depression whereby its-inner surface is flush with the inner surface of said inner wall member.

2., In a door structure, the combination of a primary inner sheet-metal wall member;

I asecondary inner sheet-metal Wall member;

inner member being provided with a peripheral depression u on its inner side; said secondary member eing bentaround the peripheral portions of said-primary and outer members to secure same in contact with each other; the inner portion of said secondary member lying in said depression whereby and an outer sheet-metal wall member; said its inner surface is flush .with the inner sur- Q face of-said inner wall member;.the outer portion of said secondary member extending inwardly from the structures periphery a greater distance upon the outside than upon the inside of said structure. a

Signed by me this 2nd day of October,

1922. v EARL v. COULSTON. 

